drivers/irqchip/irq-ts4800.c

Source file repositories/reference/linux-study-clean/drivers/irqchip/irq-ts4800.c

File Facts

System
Linux kernel
Corpus path
drivers/irqchip/irq-ts4800.c
Extension
.c
Size
4123 bytes
Lines
168
Domain
Driver Families
Bucket
drivers/irqchip
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct ts4800_irq_data {
	void __iomem            *base;
	struct platform_device	*pdev;
	struct irq_domain       *domain;
};

static void ts4800_irq_mask(struct irq_data *d)
{
	struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
	u16 reg = readw(data->base + IRQ_MASK);
	u16 mask = 1 << d->hwirq;

	writew(reg | mask, data->base + IRQ_MASK);
}

static void ts4800_irq_unmask(struct irq_data *d)
{
	struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
	u16 reg = readw(data->base + IRQ_MASK);
	u16 mask = 1 << d->hwirq;

	writew(reg & ~mask, data->base + IRQ_MASK);
}

static void ts4800_irq_print_chip(struct irq_data *d, struct seq_file *p)
{
	struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);

	seq_puts(p, dev_name(&data->pdev->dev));
}

static const struct irq_chip ts4800_chip = {
	.irq_mask	= ts4800_irq_mask,
	.irq_unmask	= ts4800_irq_unmask,
	.irq_print_chip	= ts4800_irq_print_chip,
};

static int ts4800_irqdomain_map(struct irq_domain *d, unsigned int irq,
				irq_hw_number_t hwirq)
{
	struct ts4800_irq_data *data = d->host_data;

	irq_set_chip_and_handler(irq, &ts4800_chip, handle_simple_irq);
	irq_set_chip_data(irq, data);
	irq_set_noprobe(irq);

	return 0;
}

static const struct irq_domain_ops ts4800_ic_ops = {
	.map = ts4800_irqdomain_map,
	.xlate = irq_domain_xlate_onecell,
};

static void ts4800_ic_chained_handle_irq(struct irq_desc *desc)
{
	struct ts4800_irq_data *data = irq_desc_get_handler_data(desc);
	struct irq_chip *chip = irq_desc_get_chip(desc);
	u16 status = readw(data->base + IRQ_STATUS);

	chained_irq_enter(chip, desc);

	if (unlikely(status == 0)) {
		handle_bad_irq(desc);
		goto out;
	}

	do {
		unsigned int bit = __ffs(status);

		generic_handle_domain_irq(data->domain, bit);
		status &= ~(1 << bit);
	} while (status);

out:
	chained_irq_exit(chip, desc);
}

static int ts4800_ic_probe(struct platform_device *pdev)
{
	struct device_node *node = pdev->dev.of_node;
	struct ts4800_irq_data *data;
	int parent_irq;

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->pdev = pdev;
	data->base = devm_platform_ioremap_resource(pdev, 0);

Annotation

Implementation Notes